Add solutions to 096: Reverse Words and Edit Distance by E. Choroba

Edit Distance is solved both by Text::Levenshtein and my own
implementation.

3 files changed, 134 insertions, 0 deletions

diff --git a/challenge-096/e-choroba/perl5/ch-1.pl b/challenge-096/e-choroba/perl5/ch-1.pl
new file mode 100755
index 0000000000..a314795db4
--- /dev/null
+++ b/challenge-096/e-choroba/perl5/ch-1.pl
@@ -0,0 +1,15 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+
+sub reverse_words {
+    my ($string) = @_;
+    join ' ', reverse split ' ', $string
+}
+
+use Test::More tests => 3;
+
+is reverse_words('Single'), 'Single', 'Single word';
+is reverse_words('The Weekly Challenge'), 'Challenge Weekly The', 'Example 1';
+is reverse_words('    Perl and   Raku are  part of the same family  '),
+    'family same the of part are Raku and Perl', 'Example 2';
diff --git a/challenge-096/e-choroba/perl5/ch-2a.pl b/challenge-096/e-choroba/perl5/ch-2a.pl
new file mode 100755
index 0000000000..c6b9aa9993
--- /dev/null
+++ b/challenge-096/e-choroba/perl5/ch-2a.pl
@@ -0,0 +1,16 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+
+use Text::Levenshtein qw{ distance };
+
+sub edit_distance {
+    my ($s1, $s2) = @_;
+    distance($s1, $s2)
+}
+
+use Test::More tests => 3;
+
+is edit_distance('kitten', 'sitting'), 3, 'Example 1';
+is edit_distance('sunday', 'monday'), 2, 'Example 2';
+is edit_distance('abcd', 'badc'), 3;
diff --git a/challenge-096/e-choroba/perl5/ch-2b.pl b/challenge-096/e-choroba/perl5/ch-2b.pl
new file mode 100755
index 0000000000..22d9f8b10a
--- /dev/null
+++ b/challenge-096/e-choroba/perl5/ch-2b.pl
@@ -0,0 +1,103 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+
+{   package MyDistance;
+    use Moo;
+
+    use enum qw( SAME DIFFERENT );
+    use namespace::clean;
+
+    has [qw[ s1 s2 ]] => is => 'ro';
+
+    has [qw[ width height ]] => is => 'lazy', init_arg => undef;
+    has table => is => 'ro', init_arg => undef, default => sub { [] };
+
+    sub result {
+        my ($self) = @_;
+        $self->dist(0, 0)
+    }
+
+    around BUILDARGS => sub {
+        my ($orig, $class, %args) = @_;
+        $args{$_} = "<$args{$_}>" for qw( s1 s2 );
+        $class->$orig(%args)
+    };
+
+    sub BUILD {
+        my ($self) = @_;
+        $self->fill_directions;
+        $self->fill_distances;
+    }
+
+    sub fill_directions {
+        my ($self) = @_;
+        for my $j (reverse 0 .. $self->height - 1) {
+            for my $i (reverse 0 .. $self->width - 1) {
+                $self->dir($i, $j, (
+                    substr($self->s1, $i, 1) eq substr($self->s2, $j, 1)
+                ) ? SAME : DIFFERENT);
+            }
+        }
+    }
+
+    sub fill_distances {
+        my ($self) = @_;
+        my $start = 1;
+        for my $j (reverse 0 .. $self->height - 1) {
+            for my $i (reverse 0 .. $self->width - 1) {
+                if ($start) {
+                    undef $start;
+                    $self->dist($i, $j,
+                                DIFFERENT eq $self->dir($i, $j) ? 1 : 0);
+                    next;
+                }
+                my @acc = sort { $a->[0] <=> $b->[0] }
+                               $self->accessible($i, $j);
+                $self->dist($i, $j, $acc[0][0] + $acc[0][3]);
+            }
+        }
+    }
+
+    sub accessible {
+        my ($self, $x, $y) = @_;
+        my @acc;
+        for my $ij ([1, 1], [0, 1], [1, 0]) {
+            my ($i, $j) = @$ij;
+            my $add = (SAME eq $self->dir($x, $y) && $i == $j) ? 0 : 1;
+            $i += $x;
+            $j += $y;
+            next if $i > $self->width - 1 or $j > $self->height - 1;
+
+            push @acc, [$self->dist($i, $j), $i, $j, $add];
+        }
+        return @acc
+    }
+
+    sub cell {
+        my ($self, $type, $x, $y, $val) = @_;
+        if (5 == @_) {
+            $self->table->[$x][$y][$type] = $val;
+        } else {
+            return $self->table->[$x][$y][$type]
+        }
+    }
+
+    sub dir  { shift->cell(0, @_) }
+    sub dist { shift->cell(1, @_) }
+
+    sub _build_width  { length $_[0]->s1 }
+    sub _build_height { length $_[0]->s2 }
+}
+
+sub edit_distance {
+    my ($s1, $s2) = @_;
+    my $distance = 'MyDistance'->new(s1 => $s1, s2 => $s2);
+    return $distance->result
+}
+
+use Test::More tests => 3;
+
+is edit_distance('kitten', 'sitting'), 3, 'Example 1';
+is edit_distance('sunday', 'monday'), 2, 'Example 2';
+is edit_distance('abcd', 'badc'), 3;